The 104 "class" doesn't have a class association, so far it's one guy making a lot of noise on his blog and on the french cat mailing list. The FFV (French sailing federation) refused to recognize the class due to the absence of an association representative of the owners.

In some races the race officers have been nice enough to extract a 104 results out of the handicap results, pompously presented as 'official' results on the aforementioned blog.

At one point he tried to start a set of rules, but this was rapidly removed as it prevented a lot of boat to qualify (restriction on length, width, weight, materials for hulls and spars, material for appendages...).

So the definition of the class 104 is that there is no class 104. There is just a bunch of people sailing cats with a SCHRS between 1.045 and 1.035 deciding to measure each other in real time. That's it. So you can take a A class, replace the daggerboard tips with enough lead to make it rate 1.035, put a 25kgs jockey on it and go win all 104 challenges...